Fruit thinning in 'BH-65' and 'Intenzza' papaya grown in greenhouse
Papaya (Carica papaya L.) is a tropical fruit crop originating from Central America and Mexico. Its remarkable productivity, early bearing and nutritional value are popular attributes justifying production in many areas; the crop ranks third place among the most produced tropical crops in the world, after banana and mango. Spain is the first producer of tropical fruit in Europe, leading the production for bananas, mangoes, avocados, cherimoyas and loquat. Recently, papaya has been introduced in the southeast of Spain as a complementary crop, reaching already more than 100 ha cultivated under protected cultivation. The profitability of this greenhouse production is largely determined by the choice of cultivars and the adoption of proper management techniques, well adapted to the typology of greenhouses and climate within. Efficient management of these factors are key to the establishment of an optimal crop load and proper fruit size, especially for the European market that demands medium sized papayas. Previous work has demonstrated the viability of growing papaya under greenhouses in Almería and, with its high demand in mind, we performed a fruit thinning experiment on the cultivars 'BH-65' and 'Intenzza', producing small and large fruits, respectively, with the aim of assessing the convenience of fruit thinning and the optimal number of fruit per node. Our results showed that, despite the significant differences obtained in fruit length, in soluble solids content and in skin color in response to thinning, the magnitude of the changes did not justify this practice for any of the tested cultivars; the improvements in quality did not compensate the yield losses (47 and 19% less production for 'BH-65' and 'Intenzza', respectively) and the higher cultivation costs caused by heavy thinning, leaving only one fruit per node.
Irene Salinas Romero won an ISHS student award for the best poster presentation at the V International Symposium on Papaya in Mexico in October 2017.
Irene Salinas Romero, Subtropical and Mediterranean Fruit Cultivation (AGR-222), Department of Agronomy, University of Almería, Almería, 04120, Spain, and Cajamar Experimental Station Las Palmerillas, El Ejido - Almería, 04710, Spain, e-mail: firstname.lastname@example.org